Annie Graham (Toni Collette) is an artist who recreates her familial trauma in miniature, crafting intricate dollhouses that commemorate the misery her loved ones have inflicted upon her. As the movie begins, she’s processing her lack of grief at the death, after years of dementia, of her mother, Ellen.

While Annie’s husband, Steve, played with a suitably waxen reserve by Gabriel Byrne, seems nice enough, his lukewarm geniality doesn’t offer much significant consolation. Their weed-huffing son, Peter (Alex Wolff), seems to aspire to nothing more than the life of an ordinary teen burnout and non-virgin. (Kid, you are in the wrong movie for that, let me tell you.) Finally, there’s grandma’s favorite, the Grahams’ 13-year-old daughter, Charlie (Milly Shapiro), who lurks with opaque menace behind the dead-eyed stare of a reanimated doll.

The reason to watch Hereditary is to watch Toni Collette, an actress who responds to normal events so unpredictably that you eagerly await how she’ll respond to paranormal ones. Annie seems to operate at twice the emotional and intellectual speed of everyone around her. Whether she’s delivering the eulogy for a mother she loathed or oversharing at a survivors’ support group, she sweeps unsuspecting bystanders up in the current of her perpetually unfolding internal psychodrama, then strands them several miles downstream as she moves on to the next set of unfortunates.

The spirit world is given the go-ahead to wreak havoc after Annie is coerced into conducting a séance, which vies with “head down to the basement alone” or “have sex in the woods” for the very worst decision to make when you’re in a creepy movie. Hereditary thrives on misdirection and unanticipated plot curlicues, so I won’t get too specific about what follows. But along the way to a truly gruesome climax we witness decapitation (human and avian), spontaneous combustion, demonic possession, involuntary levitation, treacherous sleepwalking, dreams masquerading as waking life, swarms of flies, a habitual tongue-clucking that’s the most unsettling aural horror device since “ba-ba-dook-dook-dooook,” and uncomfortably tense dinner-table conversation.

Critics eager to type “modern horror classic” whenever a scary movie has greater ambitions than the serial mutilation of photogenic teens have gone comparison-crazy for Hereditary: The Exorcist,Rosemary’s Baby, even “a death-metal version of Bergman’s Cries and Whispers.” But while Aster is a sure-handed conductor of terror, ping-ponging the action between the disturbing and ridiculous swiftly enough to keep you off balance and elicit both gasps and nervous laughs, he doesn’t quite stick the landing.

The grotesque tableau we end on is true to the film’s rather elaborate demonology, but shortchanges the intense, nuanced Collette performance that leads up to it. Like Annie’s dollhouses, the technique is precise and immaculate, but the human element has been eradicated.